Flash memory is a non-volatile memory, so stored data is not erased when it is powered off. Moreover, the stored data can be changed instantly and can typically be changed from thousands to tens of thousands of times in a flash memory's lifetime. Hence, flash memory has been popularly used in many electrical devices for storing data due to these factors plus its increasingly low price.
There are a lot of storage mediums today. However, the access interfaces of these storage mediums are often not compatible with each other. For example, the access interface of flash memory cannot be used to access IDE memory. Therefore, when a flash memory and an IDE memory are together used in an electrical device, it is necessary to form two access circuits for accessing the two different memories, which increases the cost and the volume of the electrical device.
Therefore, an access circuit that can access flash memory and IDE memory together is desired.